重金属镉、锌对日本血吸虫尾蚴毒性作用的观察

目的观察重金属镉、锌单独和混合存在时对日本血吸虫尾蚴的毒性作用。方法分别将40～50个尾蚴置于不同浓度(100、10、1、0.1mg/L)的镉、锌、镉/锌混合溶液中,20～25℃温箱培养,每隔30min解剖显微镜下观察尾蚴形态变化与存活数量。结果尾蚴暴露于浓度为10、100mg/L的镉、锌、镉/锌混合物溶液后,在相同观察时间内,尾蚴断尾率、死亡率显著高于对照组(P<0.01或P<0.05);尾蚴断尾率、死亡率随镉、锌、镉/锌混合溶液浓度升高而升高,以100mg/L的镉/锌混合溶液毒性作用最强。结论重金属镉、锌无论是单独存在还是混合存在,对日本血吸虫尾蚴都有一定的毒性作用,并且浓度越高,毒性作用越强。

TOXICITY OF HEAVY METALS CADMIUM AND ZINC TO CERCARIA OF SCHISTOSOMA JAPONICUM

Objective To observe the toxicity of cadmium and zinc to cercaria of Schistosoma japonicum. Methods Forty to fifty cercariae were placed in the solutions with different concentrations (100, 10, 1, 0.1 mg/L) of cadmium, zinc and both metals mixture. They were observed by dissecting microscope every 30 minutes. The pattern changes and the number of survival were recorded at the same time. Results In the solutions with concentrations of 10 mg/L and 100 mg/L of cadmium, zinc and both metals mixture, the rate of cercariae breaking tails and mortality were obviously higher than that of controls(P<0.01 or P<0.05) in the same observing time, and the rate of cercariae breaking tails and mortality increased with concentration . The toxicity to cercaria of S. japonicum was the strongest in the mixture of two heavy metals. Conclusion The single or mixture of heavy metal cadmium and zinc has significant toxicity to cercaria of S. japonicum, the toxicity increased with concentration.